I'm 40, started riding at late 33 years, I weighed 225 and wanted to get back into shape, but running resulted in lots of nagging injuries, we moved somewhere near a paved bike path and had a mongoose mtb I had bought when I was 21 and had practically zero use. It was dual suspension and it was a slog to ride on pavement, so got a hybrid, and in January of 2014 a coworker offered me a 1995 raleigh with 8 speed 105 for $100, which was a steal. Within a year of riding I had done a century, went down to 155lbs and did my first road race (not well, but I was there!). Since then I've dabbled in some road racing, got into doing CX racing a lot more, completed a 150mile gravel event, climbed over 12000ft in a single ride in Portugal, and have ridden with some really nice people in my community.
As with a lot of people who discover cycling in adulthood, I wish I had had more exposure to road cycling as a youth because my hometown is so close to some really great riding that I could have spent hours doing instead of just riding around the neighborhood and goofing around with friends (we did play lots of sports so I was active but I could have been much more active with cycling)
Nowadays I do just about all of my riding indoors, with a smart trainer and the quality of workouts I just really get a lot out of it. I'm itching to go out on some epic rides, but I try and have some time for workouts and trying to get out with my 9 y/o for 1-2hrs to complement my indoor training.